1. Field of the Invention
The present invention relates to a color image processing apparatus and, more particularly, to a color image processing apparatus having a function to automatically determine whether an original is a black-and-white original or a color original.
2. Related Background Art
In U.S. Pat. No. 4,953,012 and U.S. application Ser. No. 416,587 (Oct. 3, 1989), the applicant of the present invention has proposed a technique in a color copying apparatus in which whether an original to be read is a black and white (B/W) original or a color original is automatically discriminated. A black single color copy is executed in the case of the B/W original, and a copy using four colors of yellow, magenta, cyan, and black is performed in the case of a color original. With the above technique, the copying time and costs can be reduced.
However, according to the above proposed constructions, prior to copying the original image, the original image is pre-scanned and on the basis of the result of the discrimination obtained by the prescan, the original image is copied in either the black and white mode or in the color mode. Therefore, each time the original image is exchanged, the prescan for such a discrimination is performed.
Therefore, in the case where a plurality of originals are repetitively copied by using a recyclable automatic document feeder or where a plurality of areas in the same original are divisionally repetitively copied, the prescan for discrimination is executed many times for the same original or the same area, so that an efficiency is low.